INFLUENCE OF γ-CASEIN FRACTION WITHIN TOTALPROTEINS AMOUNT ON MILK CHEMICAL COMPOSITION

The aim of the research is improve cheese milk from Holstein cows. Main reason that hinders the production of high-quality brand cheeses by Russian cheesemakers is the lack of cheese milk for its production. Quality and structure of Caseins affect cheese milk and casein clot to form cheer cheese. It was found that the protein y-casein does not coagulate under the influence of rennet, and during cheese production it goes into thrusting, reducing the efficiency of milk use. When the mass fraction of y-casein decreases in milk proteins from 7% or more to 5.4% or less, dry matter content in milk increases by 0.12-0.32%, the mass share of fat-by 0.04-0.08%, protein-by 0.03-0.11%, including casein - by 0.06-0.24%, lactose - by 0.03-0.08%, and minerals - by 0.02-0.05%. Study milk proteins showed that mass of whey proteins, which also do not coagulate under the influence of rennet, decreases by 1.3-5.2%. There is a tendency - with decrease of γ-casein from 7.3 to 5.3%, total casein increases by 0.8-5.2%, including γ-casein by 0.7-3.6%, β-casein by 0.3-1.7%, the fraction of κ-casein by 0.2-1.9% and decrease of whey proteins by 0.8-5.2%, which increases milk and cheese handling properties.